# AD 70-21-03: Chute Coupling

- Type: Airworthiness directive
- Status: Current
- Products: Entwicklungsgemeinschaft Sport- und Segelflug Phoebus A1, Phoebus B1 and Phoebus C
- Effective: November 5, 1970
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Glider
- Amendment: 39-1088
- Registered aircraft: 14 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/841573F1884F1EC886256A38004DE7BA.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/70-21-03

## The airworthiness directive

70-21-03 ENTWICKLUNGSGEMEINSCHAFT: Amendment 39-1088. Applies to Model "PHOEBUS" A1, B1, and C Sailplanes up to and including S.N 934 which have a brake chute installed.

To prevent the rudder from becoming blocked by the back-slipping chute coupling, within the next 100 hours' time in service after the effective date of this AD, unless already accomplished, replace the chute coupling with a modified coupling in accordance with Messerschmitt - Bolkow - Blohm Service Bulletin No. Phoebus-1/70 dated April 1970, or later LBA-approved issue or an FAA-approved equivalent.

This amendment becomes effective November 5, 1970.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS G16EU](https://openairdocs.org/tcds/G16EU): Airbus Defence and Space GmbH; names 3 of 3 models: Phoebus C, Phoebus B1, Phoebus A1

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 14 (14 by airframe model, 0 by engine model)
- Makers: Bolkow 11, Waggon-Und Maschinenbau 2, Entwicklungsgemeinschaft 1

Models with the most aircraft:

- [Bolkow PHOEBUS A-1](https://openairdocs.org/model/bolkow-phoebus-a-1): 6 aircraft (airframe model)
- [Bolkow PHOEBUS C](https://openairdocs.org/model/bolkow-phoebus-c): 3 aircraft (airframe model)
- [Bolkow PHOEBUS B-1](https://openairdocs.org/model/bolkow-phoebus-b-1): 2 aircraft (airframe model)
- [Waggon-Und Maschinenbau PHOEBUS B1](https://openairdocs.org/model/waggon-und-maschinenbau-phoebus-b1): 2 aircraft (airframe model)
- [Entwicklungsgemeinschaft PHOEBUS B1](https://openairdocs.org/model/entwicklungsgemeinschaft-phoebus-b1): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/70-21-03/models.md
Every aircraft: https://openairdocs.org/ad/70-21-03/aircraft.md

Its text cites no advisory circulars or STCs.

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